VDB-322916 · CVE-2025-39715 · EUVD-2025-31512

Linux Kernel up to 6.1.148/6.6.102/6.12.43/6.16.3 LWS Call comparison

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.6	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.148/6.6.102/6.12.43/6.16.3. It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component LWS Call Handler. Such manipulation leads to comparison. This vulnerability is documented as CVE-2025-39715. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.148/6.6.102/6.12.43/6.16.3 and classified as critical. Affected by this issue is some unknown processing of the component LWS Call Handler. The manipulation with an unknown input leads to a comparison vulnerability. Using CWE to declare the problem leads to CWE-697. The product compares two entities in a security-relevant context, but the comparison is incorrect, which may lead to resultant weaknesses. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: parisc: Revise gateway LWS calls to probe user read access We use load and stbys,e instructions to trigger memory reference interruptions without writing to memory. Because of the way read access support is implemented, read access interruptions are only triggered at privilege levels 2 and 3. The kernel and gateway page execute at privilege level 0, so this code never triggers a read access interruption. Thus, it is currently possible for user code to execute a LWS compare and swap operation at an address that is read protected at privilege level 3 (PRIV_USER). Fix this by probing read access rights at privilege level 3 and branching to lws_fault if access isn't allowed.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2025-39715 since 04/16/2025. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/09/2026).

The vulnerability scanner Nessus provides a plugin with the ID 261620 (Linux Distros Unpatched Vulnerability : CVE-2025-39715), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.149, 6.6.103, 6.12.44, 6.16.4 or 6.17-rc1 eliminates this vulnerability. Applying the patch e8b496c52aa0c6572d88db7cab85aeea6f9c194d/8bccf47adbf658293528e86960e6d6f736b1c9f7/bc0a24c24ceebabb5ba65900e332233d79e625e6/9b6af875baba9c4679b55f4561e201485451305f/f6334f4ae9a4e962ba74b026e1d965dfdf8cbef8 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (261620), EUVD (EUVD-2025-31512) and CERT Bund (WID-SEC-2025-1988). Once again VulDB remains the best source for vulnerability data.

Affected

Debian Linux
Google Cloud Platform
Amazon Linux 2
Red Hat Enterprise Linux
Ubuntu Linux
SUSE Linux
Oracle Linux
NetApp FAS
NetApp AFF
NetApp ActiveIQ Unified Manager
SUSE openSUSE
RESF Rocky Linux
Open Source Linux Kernel
Microsoft Azure
Dell Secure Connect Gateway
IBM QRadar SIEM
IBM Security Verify Access
Dell NetWorker

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Comparison
CWE: CWE-697
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒